Manufacture of interfelted cellulose fiber strands



Patented Apr. 17, 1934 1,955,567

UNITED STATESYPATENT OFFICE MANUFACTURE OF INTERFELTED CELLULOSE FIBER STRANDS Milton 0. Schur and Benjamin G. Hoos, Berlin,

N. H., assignors to Brown Company,- Berlin, N. H., a corporation of Maine No, Drawing. Application December 8, 1930, Serial N0. 500,868

8 Claims. (Cl. 8-20) The subject of this invention is the manufac-- cerizing for different periods of time a twine comture of mterfelted cellulose fiber strands, and posed of four intertwisted strands of interfelted more particularly the manufacture of such wood fiber and weighing 0.2745 grams per yard: strands from relatively short and inexpensive fibers, such as wood pulp, having optimum physi- Dry Wet 60 cal ctharacteristics, including high tensile s reng h and stretching ability in both wet and A dry condition, coupled with softness and a fuzzy Tensile stretch Tee D5118 Stretch surface.

In making strands of the foregoing character, 7 gg ft ites gfi 65 the practice is to roll or to twist a narrow waterlaid ribbon of interfelted cellulose fibers made on 122 13 $2 1 3 i313 machinery of the papermaking type to round form, while the ribbon is in a damp and plastic m state.

15 The resultmg round body of waterlald when mercerization was continued for longer than 70 interfelted fibers retains its form when dried from its plastic state and has surprisingly high tensile strength and ability to withstand stretching. When composed of wood fibers, it is, however, apt to be inferior in its physical characteristics to a roving of similar weight and twist produced in the usual dry way from cotton fiber on textile machinery. While not limited thereto, our invention is thus applicable to great economic ad- 15 minutes, the results were only slightly superior to those obtained in 15 minutes. Our 15-minute mercerized product more than bears comparison in its physical characteristics with the usual cot- 75 ton fiber twines of commerce. In fact, not only did a similar weight and similarly twisted twine composed of four independent strands of cotton fiber made on textile machinery have no better vantage in the case of wood pulp stra tensile strength, but it had notably inferior so The object of the present invention is to stretchability than our 15-minute mercerized prove the physical characteristics of strands of productg waterlaid, interfelted cellulose fibers of various In determmmg the per cent streeeh as glven origins, such as wood pulp, without introducing in the foregoing table, the Speelmens were thereinto foreign materials, such as sizes or bind clamped in a Vertical S Opper testing machine .ers, which detract from their softness, fuzziness, of the usual type, but before the lower clamp and other characteristics making for similarity was tightened, a Specimen was given a Very Slight to textile rovings of cotton fiber. We have disinitial stretch by hanging a 00- ram w ight covered that the results desired may be attained thereon Y subjecting the String to the action 35 to such an extent by mercerizing the strands of of the zoo'gmm Weight, Variations due tQthe interfelted fibers that strands of such character personal factor in p ng the pec me we e composed of wood pulp may even excel in certain avoided- In other experiments, Where & 500-gram respects textile rovings of cotton fiber of equal ei ht wa u d to effect the i ti s tch weight. In speaking about strands in the speciflien 0n the t i the results w p a y 0 cation and i th appended l ims, we n the same, the per cent. stretch at the breaking either a single strand or intertwisted multiple point bein sli h lower i ll ases, as would strands, as our invention is applicable in either be exp case. Our invention is, however, especially use- In actual practice, where the damp ribbons of ful from a practical standpoint'in the manufacinterfelted fibers are rolled or furled into strand 45 ture of grocery twineconsisting of two or more form, for insta s they are carried on a Fourintertwisted strands of interfelted wood fibers, drinier wire, and are then accumulated by delivwhere ability to undergo substantial stretching ery into so-called spinning pots, such as used in without rupture is desired, as we have found that collecting rayon yarns coming fromspinning mathe mercerizationof such twines results in a chines, the annular masses or cakes of strand ma- 50 product which may have even better stretching terial collected in the pots may be advantageousability, both dry and wet, than twines of similar 1y mercerized in the pots. The walls of the pot weight, twist, and number of plies, in which the are usually perforated, so that while the pot and plies consist of cotton fiber rovings made on texthe contained cake are being spun or rotated, a tile machinery. solution of caustic soda of mercerized strength The-following table shows the effect of mermay be sprayed for the desired period of time over the inner face of the cake, centrifugal action serving to carry the solution through the mass of strand materal to effect a uniform mercerizing action. The cake may then be freed of mercerizing solution by delivering a spray of wash water over its inner surface while it is being spun or rotated along with the pot. The cake may then be dried and the dry strand material may be plied and intertwisted with similar mercerized strand material into multi-ply yarn or string. It is thus seen that after mercerization, nothing is done to the yarn or strand material to destroy the softness, fuzziness and other qualities imparted thereto by mercerization.

We are aware of the fact that the mercerization of cotton yarn made on textile machinery has long been known, but the discovery that marked benefits may be realized by mercerizing strands of waterlaid, interfelted fibers of the type of wood pulp is a surprise, especially when one pauses to refiect that cellulose fibers, in being interfelted or laid as ribbons from aqueous suspension and in being rolled or twisted in damp condition to strands, undergo manipulations quite d fferent from those performed by textile machinery on cotton fibers in the production of a roving, and further when one considers that Wood fibers under the microscope show a different physical structure and are shorter than cotton fibers. In fact, as is well known in the art, Wood pulps are invariably of an average fiber length below about 2 millimeters. Again, one might suppose that fine strands of waterlaid, interfelted fibers of relatively short length, such as wood pulp, would disintegrate or soften up to a pulp, especially when subjected to the action of an aqueous swelling agent, such as a solution of caustic soda of mercerizing strength.

An important advantage of our invention resides in the fact that it makes possible the production of yarns or twines while employing high speed machines of the papermaking type and relatively inexpensive short fibered raw materials, such as wood pulp, the resulting yarns or twines being of a quality comparing favorably with the far'rnore expensive yarns and twines'made from cotton fiber on textile machinery.

What we claim is:

1. As an article of manufacture, strand material consisting of interfelted, waterlaid cellulose fibers in mercerized condition and possessing the softness, fuzziness, and other qualities imparted thereto by mercerization.

2. As an article of manufacture, a twine consisting of at least two intertwisted strands of interfelted, waterlaid cellulose fibers in mercerized condition and possessing the softness, fuzziness, and other qualities imparted thereto by mercerization.

3. As an article of manufacture, strand material consisting of a rounded ribbon of interfelted wood fibers in mercerized condition and possessing the softness, fuzziness, and other qualities imparted thereto by mercerization.

4. As an article of manufacture, a twine consisting of at least two strands of intertwisted, rounded ribbons of interfelted wood fibers in mercerized condition and possessing the softness, fuzziness, and other qualities imparted thereto by mercerization.

5. A process which comprises treating strand material consisting of a rounded ribbon of interfelted, waterlaid cellulose fibers with a mercerizing liquor, and washing the liquor from such material and then drying it while preserving therein the softness, fuzziness, and other qualities imparted thereto by mercerization.

6. A process which comprises treating a twine consisting of at least two rounded ribbons of interfelted wood fibers with a mercerizing liquor, and washing the liquor from such material and then drying it while preserving therein the softness, fuzziness, and other qualities imparted thereto by mercerization.

'7. A process which comprises spraying mercerizing liquor over the inner surface of an annular mass of strand material consisting of at least one rounded ribbon of interfelted, waterlaid cellulose fibers while the mass is being spun or rotated in a spinning pot whose walls are perforated, then spraying wash water over the inner surface of the mass while it is thus being spun, and drying the mass.

8. A process which comprises spraying mercerizing liquor over the inner surface of an annular mass of strand material consisting of a rounded ribbon of interfelted, waterlaid cellulose fibers while the mass is being spun or rotated in a spin- -ning pot whose walls are perforated, then spraying wash water over the inner surface of the mass while it is thus being spun, drying the washed mass, and plying and intertwisting the dry strand material with similar strand material into multiply yarn or string.

MILTON O. SCHUR. BENJAMIN G. HOOS. 

